Vertebral arch (arcus vertebrae) forms protection for the spinal cord and it is the reason that it could also be called the neural arch. It is the posterior part of the vertebra which consists of:
Pedicle of vertebral arch
Pedicle of vertebral arch (pedunculus arcus vertebrae) which projects posterolaterally from the body and it is fused with the second one in the midline. On the pedicles of the following structures that may be identified:
- The superior vertebral notch (smaller) and the inferior vertebral notch (deeper) which form the in-tervertebral foramen (made up of the inferior vertebral notch from vertebra above and the superior vertebral notch from the vertebra below) when the vertebrae are articulated. The intervertebral foramen is a space between pedicles of adjacent vertebrae for passage of the spinal nerve (see Fig. 2-33)
Lamina of vertebral arch
Lamina of vertebral arch (lamina arcus vertebrae) extends posteromedialy from pedicle of vertebral arch, and it connects with the second one in the midline.
There are seven processess (three types), which arise from the vertebral arch.
- Spinous process (processus spinosus) is an unpaired process which projects backwardly in the midsagittal plane from the union point of the vertebral arch laminae
- Transverse process (processus transversus) is a paired process which projects laterally on each side from the junction of the lamina and pedicle. They form bony levers for the attachment of deep back muscles.
- Superior articular process (processus articularis superior) is a paired process and it projects superiorly on each of the pedicle (it projects superiorly and in different regions, the superior, anterior or medial articular surface is found on it for the cervical, thoracic and lumbar vertebrae respectively).
- Inferior articular process (processus articularis inferior) is a paired process that projects inferiorly on each side of the pedicle (it project inferiorly and in different regions, the inferior, posterior or lateral articular surface is found on it for the cervical, thoracic and lumbar vertebrae respectively).